A UK TV channel has been re-running this here and have just shown an episode, The Visitor, where Sisko meets a much-older Jake.
Not the most gripping episode, but the future includes an older and noticeably-wrinkly Jadzia.
But didn't she get killed in a later episode on the main timeline?
The main theme of that episode (DS9: The Visitor) is that Jake's father was trapped in time. By freeing him, Jake caused that particular timeline to cease to exist.
JAKE SR: You see, Melanie, after the last attempt to rescue my father failed, I spent months trying to figure out what went wrong. Eventually, I came to understand the nature of what was happening to him. It was as if he was frozen in time at the moment of the accident, and the link between us was like an elastic cord. Every so often the cord would go taut enough to yank him forward into my time. But only for a few minutes. I realised that if my motion through time came to a stop, the cord would go slack and he'd be lost in subspace forever. But if I could cut the cord when the link was at its strongest, while we were together, he'd return to the moment of the accident.
Given that Jadzia died as a direct consequence of Ben's ongoing feud with Dukat, it would appear that his disappearance resulted in her not dying in season 6
